U.S. Pat. No. 5,196,279 to Tarascon discloses the use and advantages of intercalated lithium manganese oxide (Li.sub.x Mn.sub.2 O.sub.4) spinel in forming secondary lithium batteries. Heretofore, lithium manganese oxide (Li.sub.x Mn.sub.2 O.sub.4) based intercalation compounds were produced by a fairly lengthy process. The accepted process for producing such intercalation compound called for mixing the base component of lithium carbonate Li.sub.2 CO.sub.3 and manganese dioxide MnO.sub.2 for approximately 48 hours to insure thorough mixing of the material. The mixing was conventionally done by a conventional rotary mixer.
The mixing was then followed by several heating and cooling steps to calcine the material. The material was calcined at a temperature of about 800.degree. C. or below. The final cooling of the material (from about 800.degree. C. to about 500.degree. C.) was gradual, taking about 99 hours. The total time for the aforementioned conventional process was about 300 to 400 hours. Not only is such a process time-consuming, it also utilizes expensive equipment and significant amounts of energy.
The present invention overcomes these and other problems and provides a process for producing lithium manganese oxide (Li.sub.x Mn.sub.2 O.sub.4) spinel intercalation compounds that require significantly shorter processing time and reduce the overall cost, while providing a high-performance material.